1. Field of the Invention
This invention relates to the manufacture of denture bases, and more particularly to a method of manufacturing quality denture bases easily through the use of photocurable resin compounds. The present invention is also applicable to the manufacture of metallic denture bases, resinous denture bases, overall dentures and partial dentures.
2. Description of the Prior Art
Several ways of manufacturing denture bases are well knonw: (1) thermal polymerization wherein a mixture of polymer powder and liquid monomer is cast into a negative mold, as disclosed in W. German Pat. No. 940,493, Japanese Patent Publication 46/40108, etc.; (2) room temperature polymerization wherein a mixture of polymer powder, liquid monomer and a polymerization agent is cast into a negative mold, see, for example, W. German Pat. No. D 85578, Swiss Pat. No. 74466 and French Pat. No. 883679; and (3) injection molding wherein polymer pellets are heated and melted, for example, Japanese Patent Publication No. 42/4833.
The serious disadvantages of those conventional procedures, however, are that (a) manufacture of the negative mold in advance is indispensable, (b) procedures for casting or injection are laborious and require rather expensive facilities, (c) after hardening, removal of the mold is time- and labor-consuming, (d) polishing subsequent to removal of the mold is also indispensable, and (e) the resin tends to shrink and deform during the curing or hardening process with an accompanying decline in accuracy of the molding.